package com.iraeta.uitl;

import cn.hutool.core.date.DateUtil;
import cn.hutool.core.util.StrUtil;
import com.iraeta.Config;
import com.iraeta.common.Constants;
import com.iraeta.common.ServiceException;
import org.apache.commons.io.FilenameUtils;
import org.springframework.web.multipart.MultipartFile;

import java.io.File;
import java.io.IOException;
import java.nio.file.Paths;
import java.util.Arrays;
import java.util.Date;
import java.util.Objects;

public class FileUploadUtils {

    /**
     * 默认大小 50M
     */
    public static final long DEFAULT_MAX_SIZE = 50 * 1024 * 1024;

    /**
     * 默认的文件名最大长度 100
     */
    public static final int DEFAULT_FILE_NAME_LENGTH = 100;

    /**
     * 根据文件路径上传
     *
     * @param baseDir 相对应用的基目录
     * @param file 上传的文件
     * @return 文件名称
     * @throws IOException
     */
    public static final String upload(String baseDir, MultipartFile file) throws IOException
    {
        try
        {
            return upload(baseDir, file, MimeTypeUtils.DEFAULT_ALLOWED_EXTENSION);
        }
        catch (Exception e)
        {
            throw new IOException(e.getMessage(), e);
        }
    }

    /**
     * 文件上传
     *
     * @param baseDir 相对应用的基目录
     * @param file 上传的文件
     * @param allowedExtension 上传文件类型
     * @return 返回上传成功的文件名
     * @throws IOException 比如读写文件出错时
     */
    public static final String upload(String baseDir, MultipartFile file, String[] allowedExtension) throws IOException
    {
        int fileNamelength = Objects.requireNonNull(file.getOriginalFilename()).length();
        if (fileNamelength > FileUploadUtils.DEFAULT_FILE_NAME_LENGTH)
        {
            throw new ServiceException("文件大小异常");
        }

        assertAllowed(file, allowedExtension);

        String fileName = extractFilename(file);

        String absPath = getAbsoluteFile(baseDir, fileName).getAbsolutePath();
        file.transferTo(Paths.get(absPath));
        return getPathFileName(baseDir, fileName);
    }

    public static final File getAbsoluteFile(String uploadDir, String fileName) throws IOException
    {
        File desc = new File(uploadDir + File.separator + fileName);

        if (!desc.exists())
        {
            if (!desc.getParentFile().exists())
            {
                desc.getParentFile().mkdirs();
            }
        }
        return desc;
    }

    public static final String getPathFileName(String uploadDir, String fileName) throws IOException
    {
        return Constants.RESOURCE_PREFIX  + "/" + fileName;
    }

    /**
     * 文件大小校验  文件类型校验
     *
     * @param file 上传的文件
     * @return
     */
    public static final void assertAllowed(MultipartFile file, String[] allowedExtension)
    {
        long size = file.getSize();
        if (size > DEFAULT_MAX_SIZE)
        {
            throw new RuntimeException("文件太大");
        }
        String extension = getExtension(file);
        if (allowedExtension != null && !Arrays.asList(allowedExtension).contains(extension))
        {
            throw new RuntimeException("文件类型不匹配");
        }
    }

    /**
     * 编码文件名
     */
    public static final String extractFilename(MultipartFile file)
    {
        return StrUtil.format("{}/{}_{}.{}", DateUtil.format(new Date(), "yyyy/MM/dd"),
                FilenameUtils.getBaseName(file.getOriginalFilename()), Util.getBusinessNo(), getExtension(file));
    }

    /**
     * 获取文件名的后缀
     *
     * @param file 表单文件
     * @return 后缀名
     */
    public static final String getExtension(MultipartFile file)
    {
        String extension = FilenameUtils.getExtension(file.getOriginalFilename());
        if (StrUtil.isEmpty(extension))
        {
            extension = MimeTypeUtils.getExtension(Objects.requireNonNull(file.getContentType()));
        }
        return extension;
    }
}
